Through space and time: An examination of motion in multiple object tracking
Object correspondence is the process by which the visual system matches the identities of objects to their locations to form stable percepts. Object correspondence is useful when we watch a sporting event, like basketball, in which the players move. The visual system binds the identities of the players to their new locations to maintain their identities as they move. The visual system could perform this task using only position information by updating the locations of each object using a proximity rule. Alternatively, the visual system may use motion information to bind the identities to the new locations. For example, motion could be used to predict the future locations of moving objects. One way cognitive psychologists study this process in human participants is with the multiple object tracking task. In this task, participants track target objects as they move among identical distractors. The work in this dissertation examined whether or not motion is used during multiple object tracking. In my tracking display, textured objects were presented and I manipulated the direction of the texture motion relative to the direction of the object motion. I found that tracking was impaired when the texture motion conflicted with the object motion because the mental representations of motion did not match the physical motion of objects in the display. I concluded that the visual system depends on motion representations of targets and distractors to solve the object correspondence problem during tracking.